When a computer is “booted”, an operating system is loaded into memory from a hard disk drive. This means that the HDD must first be spun up and made operational, and then data transferred from disk to memory, lengthening the time to boot the computer.
In addition to the conventional functions of a personal computer (such as, e.g., word processing, spreadsheet generation, etc.) that are afforded by the primary operating system (such as, e.g., Windows 7), some computers are configured to execute functions that may otherwise be performed by special purpose devices. For example, some notebook computers are configured to be used as simple DVD players, or as wireless telephones, or as email devices. In each case, the present invention recognizes that a simpler secondary operating system with correspondingly limited device drivers may be stored on the HDD to be booted in lieu of the computer's primary operating system. In this way, if all a user wishes to do is to use the computer for a relatively simple function and then shut the computer down, booting time can be reduced because only the relatively smaller secondary operating system associated with the desired function need be booted into memory.
As recognized herein, however, booting under such circumstances still requires the HDD to be spun up. Although booting time is reduced, it still requires some period of time, and furthermore spinning up a HDD consumes energy, which is particularly undesirable for battery-powered computers. Nevertheless, because existing basic input-output systems (BIOS) of computers (the small programs that initiate operating system booting and that are not borne on the HDD but instead are stored in relatively small solid state memory) typically are configured to access a HDD to obtain the operating system, it remains desirable to boot from a HDD, since that is where BIOS expects the operating system to be. With these recognitions in mind, the invention herein is provided.